Dark Ritual

Sinkhole

Fear

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Enchanted creature has fear. (It can't be blocked except by artifact creatures and/or black creatures.)

Scavenging Ghoul

At the beginning of each end step, put a corpse counter on Scavenging Ghoul for each creature that died this turn.
Remove a corpse counter from Scavenging Ghoul: Regenerate Scavenging Ghoul.

Weakness

Enchant creature
Enchanted creature gets -2/-1.

Plague Rats

Plague Rats's power and toughness are each equal to the number of creatures named Plague Rats on the battlefield.

Unholy Strength

Enchant creature
Enchanted creature gets +2/+1.

Scathe Zombies

Mind Twist

Target player discards X cards at random.

Howl from Beyond

Target creature gets +X/+0 until end of turn.

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Terror

Destroy target nonartifact, nonblack creature. It can't be regenerated.

Frozen Shade

{B}: Frozen Shade gets +1/+1 until end of turn.

Swamp

Raise Dead

Return target creature card from your graveyard to your hand.

Paralyze

Enchant creature
When Paralyze enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.
At the beginning of the upkeep of enchanted creature's controller, that player may pay {4}. If the player does, untap the creature.

Lich

As Lich enters, you lose life equal to your life total.
You don't lose the game for having 0 or less life.
If you would gain life, draw that many cards instead.
Whenever you're dealt damage, sacrifice that many nontoken permanents. If you can't, you lose the game.
When Lich is put into a graveyard from the battlefield, you lose the game.

Cursed Land

Enchant land
At the beginning of the upkeep of enchanted land's controller, Cursed Land deals 1 damage to that player.

Drudge Skeletons

{B}: Regenerate Drudge Skeletons. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)